REINVENTING ADDITIVE

Laura Griffiths speaks to Richard Hague at the University of Nottingham about the opportuities for multi-material, functional additive manufacturing.

The job of a researcher is to keep reinventing and continue to ask “what’s next?” For Richard Hague, Professor of Additive Manufacturing and Director of the Centre for Additive Manufacturing (CfAM) at the University of Nottingham, that question has been at the core of numerous projects undertaken at the Centre over the last decade where the ‘what’ is poised to be multi-material, functional additive manufacturing (AM).

TCT: Hi Richard. Tell us, why multifunctional additive manufacturing?

RH: We wanted to do something a little bit different. For me, if you're going to be a leading research group, you need to be doing leading research. I didn't want to be a group that continued just to make shapes, which we probably were in the 1990s, and wanted to transform the group to be much more of a science-based activity that was at the cutting edge, doing the materials and process development for additive. So, we hit on this idea of multi-material, multifunctional stuff, which no one was really doing at the time.

For me, it's always been not what it is, it's how it's made, I’m much more interested in the process, and industry and people will come along and use it for different applications. You can see it in single material conventional additive manufacturing today, the kind of applications we get today are incredible and no one would have imagined that 20 years ago when we first started doing additive manufacturing research.

TCT: Can you tell us about what you’re currently working on?

RH: We have various projects looking at the printing of functional materials – too many! We have really amazing partners across the industrial spectrum, […] AstraZeneca, GSK and Pfizer, those kinds of pharmabased companies, we also work with the BAE Systems and other large aerospace companies on defence and automotive, and those kinds of areas. So, we have a range and I think some of the things that we've been doing that everyone will be interested in, I think, is printing of magnetics and magnetic parts for electric motors. There's a real opportunity for additive to be able to create more efficient electric motors. And we all need to have more efficient electric motors in our cars; they go faster, they're lighter, more efficient, use less electricity, same power. So we’ve done really nice work looking at the optimization of electrical motors, and we’re very lucky to have connected research groups here at Nottingham. We have the Power Electronics and Machines group here who are experts on electrical machine design. We do the processing and material side of additive and we can work with them on their application. It's the same at the pharmacy department here, the top one in the UK, top three in the world pharmacy department, so we're really lucky to be able to work with them.

TCT: What potential do you see multifunctional AM having? What kind of applications could it open up that perhaps weren’t possible before?

RH: That’s a big question. If I had the answer for every single thing that could be done with additive, I’d be much wealthier than I am now! The potential for printing batteries, I think that's got some real scope. We can have a much higher surface area within the batteries so, printing solid state batteries that last longer. I think that metamaterials have got real potential where we can produce structures that just don't appear in nature naturally and perform in a different way, both mechanical and electromechanical. I'm personally less interested in just making structure. We've seen some really lovely examples and been involved in some really lovely examples of creating single material structure but I think research in AM has gone beyond that. We need to combine both function and structure and that could be across a range of different applications that have electronic, electromagnetic, pharma, bio, whatever, and I think the opportunities are huge.

TCT: What are the main challenges with multi-material, multi-functional AM?

RH: There are temperature limitations and there are viscosity limitations that you have. There's the fact that you're depositing some materials that are much thinner in layers. The functional layers are very often much thinner because they often contain nanoparticulate, which produce extremely thin, couple of micron thick layers compared to the structural layer that you're sticking around it. So there's this mismatch and then you’ve got to functionalize that functional material in process because it's going to get entrapped by the functional material that you're likely wrapping around it.

I think one of the challenges we have with additive, it's conceptually quite a simple thing to understand. In reality, doing it is quite hard, even for single materials. And with multi materials, it's ten times worse.

TCT: As a researcher, how challenging is it to turn a research project into something that can be adopted by industry?

RH: We've had a real focus in the last ten years or so on getting publications and academic journal publications out. The UK is generally pretty good at getting really excellent journal publications, and our rate of publication in the UK is very, very high. Not just us, groups such as Sheffield and Liverpool have got really good reputations. It's kind of an AM research superpower but translating that into end product is quite hard.

First of all, it's quite hard patenting things within universities because the route to getting patents is quite complicated. And then setting up spin out companies is quite hard. So you really have to work very closely with industry and all [of our] grants have very strong industrial collaborators.

There are really nice examples of it working but I don't think we have enough of it. To a certain extent, that’s because academics are motivated to write journal publications rather than patents and that's because their careers are based on it. So, if a researcher wants to move forward in their career, they have to have a certain amount of journal publications and that's how they’re judged not necessarily on patents because they take a long while to come to fruition in terms of licencing, etc. Personally, I think that we should have much more incentives to take our research out and patent it and exploit it, and it should be easier to set up a spinout company.

TCT: What are your ambitions for the year, what can we expect to see coming out of the Centre next?

RH: We're looking to expand [materials that you have for polymeric systems] with real engineering grade polyurethanes, silicones and polycarbonate materials that we can produce on these additive processes and that will be fantastic. So, I'm looking forward to really pushing the research forward, and taking our companies to the next level as well.

That's one of the joys of being an academic. In the end, you can think of an idea and you have to be able to write it up, you have to be able to convince people that it's worth funding, but then you get funded for it and you get to work with fantastic colleagues, fabulous industry and a really nice working environment. It doesn’t get a lot better, really. You're very much in control of your own destiny, and you get to work with some clever people and that's the most interesting thing.

Listen to the interview in full on the Additive Insight podcast: mytct.co/CfAM